Sir,
Four types of human dental stem cells have been isolated. Dental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHED), stem cells from apical papillae (SCAP), periodontal ligament stem cells (PDLSCs). Studies have demonstrated that gene variations occurred within the different sources of the same cells and these variations determine their lineage propensity toward specific destination. Stem cells of deciduous teeth retained their plasticity over the passages, where as permanent stem cells lost their plasticity and were shown to be more committed towards neuronal lineage.[1] For successful regeneration, revascularization is necessary. For endodontic treatment it is recommended to create a blood clot after the infection control procedure. The Proangiogenic factors, i.e., vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF-2) play essential roles in neovascularization. The expression of specific antigens for endothelial cells, including von-Willebrand factor, CD31, CD146 side population cells and angiotensin converting enzyme is observed, suggesting an angiogenic potential for DPSCs.[2]
Hunang et al, found Dental stem cells when seeded onto a poly-d,l,-lactide and glycolide (PLG) scaffold, which was then inserted into the fabricated tooth root. The cell-seeded tooth fragments were transplanted subcutaneously and harvested after three to four months. Analyses of the harvested implants revealed the formation of well-vascularized soft tissue in the root canal space.[3]
DPSCS, SHED, SCAP are derived from neural crest mesenchyme. Therefore, these cells may act as source for neural cells. These stem cells have expressed a variety of neural markers like nestin, glutamine and decarboxylase, neuronal nuclei, glial fibrillary acidic protein, neurofilament M, 2’,3’-cyclic nucleotide-3’-phosphodiesterase.[4,5]
Further understanding of stem cell research and positive in vivo studies will lead to a ground-breaking treatment modality in endodontics.
References
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